| Inland Marine Industries Inc Milling, Turning, Waterjet, Punching, Bending, Welding, Grinding, Finishing · ISO 9001, ITAR | Hayward, CA | MillingTurningWaterjetPunchingBendingWeldingGrindingFinishing | ISO 9001, ITAR |
| Innov8 Manufacturing LLC Milling, Turning, Welding, Grinding · ISO 9001 | Farmington, MI | MillingTurningWeldingGrinding | ISO 9001 |
| Insaco Inc Milling, Grinding · ITAR | Quakertown, PA | MillingGrinding | ITAR |
| Inter-Precision Mold Inc Milling, Turning, Welding, EDM, Grinding, Assembly | El Paso, TX | MillingTurningWeldingEDMGrindingAssembly | - |
| International Precision Machining, Inc Milling, Turning, Grinding · ISO 9001, AS9100 | Waite Park, MN | MillingTurningGrinding | ISO 9001, AS9100 |
| Inventex, Inc Grinding | W Nottingham, NH | Grinding | - |
| Iq Manufacturing LLC Milling, Stamping, EDM, Grinding · ISO 9001 | Auburn Hills, MI | MillingStampingEDMGrinding | ISO 9001 |
| Iridium Manufacturing Milling, Turning, Waterjet, EDM, Grinding · ISO 9001 | Washington, MI | MillingTurningWaterjetEDMGrinding | ISO 9001 |
| Irwin Automation Inc Milling, Turning, Welding, EDM, Grinding | Greensburg, PA | MillingTurningWeldingEDMGrinding | - |
| Issi Engineering and Machining, LLC Grinding · ISO 9001 | Evansville, IN | Grinding | ISO 9001 |
| Ital-Tech Machined Products, LLC Milling, Turning, Welding, Grinding · ISO 9001, ITAR | Groveland, MA | MillingTurningWeldingGrinding | ISO 9001, ITAR |
| J W Machine & Fab LLC Milling, Turning, Welding, Grinding | Fountain Inn, SC | MillingTurningWeldingGrinding | - |
| Jacksonville Machine, Inc Milling, Turning, Welding, Grinding · ISO 9001 | Jacksonville, IL | MillingTurningWeldingGrinding | ISO 9001 |
| Jaffa Precision Engineering Inc Milling, Turning, Swiss, Welding, Grinding, Finishing · ISO 9001 | Riverside, CA | MillingTurningSwissWeldingGrindingFinishing | ISO 9001 |
| Jars Inc Milling, Waterjet, Bending, Welding, EDM, Grinding, Finishing | San Fernando, CA | MillingWaterjetBendingWeldingEDMGrindingFinishing | - |
| JC Custom Machining & Design Inc Milling, Turning, Welding, Grinding | Hillsboro, OR | MillingTurningWeldingGrinding | - |
| JDM Machining Inc Milling, Turning, Swiss, Bending, Welding, EDM, Grinding · ISO 9001, AS9100 | Staples, MN | MillingTurningSwissBendingWeldingEDMGrinding | ISO 9001, AS9100 |
| Jeglinski Group Inc Milling, Turning, Welding, EDM, Grinding, Assembly · ISO 9001 | Meadville, PA | MillingTurningWeldingEDMGrindingAssembly | ISO 9001 |
| Jenkins Machine Inc Milling, Turning, EDM, Grinding, Finishing | Bethlehem, PA | MillingTurningEDMGrindingFinishing | - |
| JMS Machine, Inc Milling, Turning, EDM, Grinding | Columbia City, IN | MillingTurningEDMGrinding | - |
| Joels Machine Shop Inc Milling, Turning, Grinding | El Monte, CA | MillingTurningGrinding | - |
| Johnson Manufacturing Milling, Turning, Grinding · AS9100 | Huntington Beach, CA | MillingTurningGrinding | AS9100 |
| Johnson Manufacturing Systems LLC Milling, Turning, Welding, Grinding | Miamisburg, OH | MillingTurningWeldingGrinding | - |
| Jolar Machine Shop Milling, Grinding, Finishing · ISO 9001 | Dickson City, PA | MillingGrindingFinishing | ISO 9001 |
| Jonaco Machine Inc Milling, Turning, Swiss, EDM, Grinding · ISO 9001 | Chaska, MN | MillingTurningSwissEDMGrinding | ISO 9001 |
| Jonesboro Tool & Die Co Inc Milling, Turning, Laser, Waterjet, Bending, Welding, Stamping, EDM, Grinding · AS9100, ITAR, CMMC | Jonesboro, AR | MillingTurningLaserWaterjetBendingWeldingStampingEDMGrinding | AS9100, ITAR, CMMC |
| K & B Machining Inc Milling, Turning, Laser, Grinding, Finishing · ISO 9001, ITAR | Claremore, OK | MillingTurningLaserGrindingFinishing | ISO 9001, ITAR |
| Kennebec Technologies Milling, Grinding, Assembly | Augusta, ME | MillingGrindingAssembly | - |
| Kent Machine Milling, EDM, Grinding | Indianapolis, IN | MillingEDMGrinding | - |
| Kentucky Machine & Tool Co Milling, Turning, Waterjet, Welding, Grinding | Louisville, KY | MillingTurningWaterjetWeldingGrinding | - |
| Ketchie-Houston, Inc Milling, Turning, EDM, Grinding · ISO 9001, AS9100 | Concord, NC | MillingTurningEDMGrinding | ISO 9001, AS9100 |
| Keystone Machine & Fab, Inc Milling, Turning, EDM, Grinding | Grafton, OH | MillingTurningEDMGrinding | - |
| KF Precision Honing LLC Milling, Grinding · ITAR | Antigo, WI | MillingGrinding | ITAR |
| Ki Machine Tools & Productions Inc Milling, Turning, Bending, Welding, EDM, Grinding | Loves Park, IL | MillingTurningBendingWeldingEDMGrinding | - |
| Kineo, Inc Milling, Turning, EDM, Grinding, Finishing · ISO 9001, ISO 13485 | Colorado Springs, CO | MillingTurningEDMGrindingFinishing | ISO 9001, ISO 13485 |
| Kinetic Engine Systems Milling, EDM, Grinding | Phoenix, AZ | MillingEDMGrinding | - |
| Kinross Fab & Machine Inc Milling, Turning, Laser, Welding, Grinding, Finishing | Kincheloe, MI | MillingTurningLaserWeldingGrindingFinishing | - |
| Kirsh Manufacturing Inc Milling, Turning, Welding, Grinding, Finishing · ISO 9001, ITAR | Tucson, AZ | MillingTurningWeldingGrindingFinishing | ISO 9001, ITAR |
| Korzan Enterprises Inc Milling, Turning, Waterjet, Welding, EDM, Grinding, Finishing | Orchard Park, NY | MillingTurningWaterjetWeldingEDMGrindingFinishing | - |
| Kte Holdings LLC Milling, Turning, Welding, Grinding, Finishing | Mableton, GA | MillingTurningWeldingGrindingFinishing | - |
| Kuhn Tool & Die Co Milling, Waterjet, Welding, Stamping, EDM, Grinding | Meadville, PA | MillingWaterjetWeldingStampingEDMGrinding | - |
| L & R Machine Inc Milling, Turning, Grinding | Rancho Cucamonga, CA | MillingTurningGrinding | - |
| L.a. Martin Company Milling, Turning, Bending, Welding, Grinding, Finishing · ISO 9001 | Dearborn, MI | MillingTurningBendingWeldingGrindingFinishing | ISO 9001 |
| Lam Precision, Inc Milling, Grinding · AS9100 | Anaheim, CA | MillingGrinding | AS9100 |
| Lancaster Design & Machine Milling, Welding, Grinding · ISO 9001 | Dacula, GA | MillingWeldingGrinding | ISO 9001 |
| Lange Grinding & Machining, Inc Milling, Turning, Welding, Grinding | Streetsboro, OH | MillingTurningWeldingGrinding | - |
| Larkin Precision, LLC Laser, Grinding | Kent, WA | LaserGrinding | - |
| Laser Cutting Co Milling, Laser, Bending, Welding, Grinding, Finishing · ISO 9001 | Harrison Township, MI | MillingLaserBendingWeldingGrindingFinishing | ISO 9001 |
| Lawruk Machine & Tool Milling, Turning, Welding, Grinding · ISO 9001 | Altoona, PA | MillingTurningWeldingGrinding | ISO 9001 |
| Lawson Precision Machining, Inc Milling, Turning, Welding, Grinding · ISO 9001 | Bucyrus, OH | MillingTurningWeldingGrinding | ISO 9001 |